Multicast transmissions may be directed to a wide variety of client devices, which may support a heterogeneous set of wireless communications standards and capabilities within those standards. Multicast access points, such as those implementing Wi-Fi networks based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of communication standards, are typically configured to select data rates for multicast transmissions to ensure compatibility across all of the above-mentioned standards, which may impede the performance of certain multicast applications.
Access points implementing the 802.11 standards are typically configured to select minimum data rates for multicast transmissions. That is, a multicast transmission is sent at a data rate corresponding to the minimum rate specified by the wireless standard supported by the least-capable client device. Compatibility with all client devices is therefore achieved at the cost of performance. Some multicast applications, such as video streaming, multi-party telephony and the like, suffer from reduced performance (e.g. pauses, delayed loading of buffer data, increased latency and the like) at such minimal data rates. For example, an access point operating in an 802.11b/g/n mode (that is, supporting the IEEE standards 802.11b, 802.11g, and 802.11n in the 2.4 GHz frequency band) is conventionally configured to set the data rate to 1 megabit per second (Mbps) for multicast transmissions, corresponding to the minimum supported data rate mandated by the 802.11b standard. At a data rate of 1 Mbps, however, applications such as the video streaming and multi-party telephony applications mentioned above may suffer from reduced performance, impeding the usability of those applications.
Performance issues such as those mentioned above may be resolved by disabling certain data rates at the access point and thus resulting in the selection of a greater minimum data rate for multicast transmissions. However, supported data rate settings at access points are typically applied to all transmissions. Therefore disabling low data rates will also prevent the access point from communicating with certain legacy client devices to provide other services for which the lower data rates (e.g. the 1 Mbps mentioned above) would have been suitable.
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